fix(issue-52): use pull request github api url as source

[lampajr]

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fix #52

This is going to fix a regression introduced after gitlab extension, actually since version v3.1.0.

Regression: it was no longer possible to provide github api pull request url as pr source, e.g, https://api.github.com/repos/owner/repo/pulls/1

Referenced pull requests

Checklist

• Tests added if applicable.
• Documentation updated if applicable.

Note: dist/cli/index.js and dist/gha/index.js are automatically generated by git hooks and gh workflows.